The present disclosure relates to battery packs for automotive vehicles. More particularly, the present disclosure relates to battery cooling apparatus using a fluid state medium to cool battery packs having at least one stacked array of rechargeable battery cells.
Electric vehicles, including hybrid electric vehicles, have electric motors for propelling the vehicles along roadways, for example, and these electric motors typically rely upon onboard rechargeable batteries as their energy source. Battery packs having a fairly large number of individual rechargeable battery cells are frequently used with such vehicles. An example of a battery cell that is used in electric vehicles is a lithium ion battery cell. When recharging and when discharging to provide power to the electric motors of electric vehicles, the battery cells generate heat that needs to be removed in order to maintain the battery cells below their maximum allowable temperatures so that the battery cells are not damaged or destroyed by the heat. When removing heat from battery packs, it is desirable but not necessary to have the faces of each of the battery cells maintained at a fairly uniform temperature.
It is known in the art that liquid-cooling provides significant convection coefficients and can be used to cool battery packs. However, some of these systems include dozens or hundreds of liquid-sealed connections. This proliferation of connections may add cost and risk of leakage to the liquid coolers for use with battery packs. Accordingly, there is a need for an improved liquid cooled battery pack apparatus.